Fig. 8. Binding of recombinant structural mimics of human integrin ß1 and ß3 cytoplasmic tails to proteins in lysates of chicken osteoclast precursor cells. Integrin sequences of the recombinant proteins are depicted at the bottom, including those containing a tyrosine-alanine point mutation at a conserved NPXY motif. Via an N-terminal His-Tag sequence, these proteins were bound to a Ni²⁺-resin and incubated with cell lysates. Bound cellular proteins were eluted together with the recombinant proteins from the resin and analyzed by western blotting with antibodies against Pyk2, Talin and Paxillin. Coomassie Blue staining (Coom.) was used to verify that comparable amounts of recombinant proteins were present in each experiment. Supernatants of the binding reactions were also analyzed (non-bound). (C, control Ni²⁺-resin used without any added His-tagged protein; n.d., not done).